The present invention relates to liquid material dispensers, and particularly to dispensers for dispensing medicaments at small, precisely-controlled rates. The invention is especially useful in a dispenser including an electrolytic cell generating a gas in accordance with t rate the liquid is to be dispensed, such as described in our prior U.S. Pat. Nos. 5,062,834 and 5,090,963, and it is therefore described below particularly with respect to such a dispenser.
There are many applications, such as drug delivery systems, requiring the dispensing or delivering of a liquid at a predetermined, precisely-controlled rate. Electrolytic pumps, such as described in our above U.S. patents, have been developed for this purpose. These pumps, however, generally include relatively large pumping chambers, and therefore their pumping rates may be significantly influenced by pressure and temperature changes particularly when the dispenser is used over long periods of time and/or under varying ambient conditions.
It would therefore be desirable to provide a liquid material dispenser or pump of a construction which may include a pumping chamber of relatively small volume so that the rate of delivery of the liquid is less sensitive to pressure and temperature changes.